The usefulness of a semispecific PCR system for the evaluation of genetic diversity among selected cultivars of wheat (Triticum aestivum L.) and triticale (x Triticosecale Wittm.) was investigated. A comparison was made of the diversity among cultivars of both species as revealed by primers targetting the semi-conservative sequences of the intron-exon junction. The main purpose of the study was the selection of the most informative primers from among the exon targetting (ET) and intron targetting (IT) primers of 12 to 18 bases in length. For triticale, the most satisfactory results were obtained using ET and IT primers of 18 bases in length. In wheat, complex and polymorphic banding patterns were generated by primers belonging to both groups, regardless of their length.